Automatic sprinkler system



Aug. 27, 1940. w. B. GRIFFITH AUTOMATIC SPRINKLER SYSTEM Filed May 24,1939 iv f UNIT Patented Aug. 27, v1940 per rrics 2,212,562 eurer/retirosenr-unten srs'rnru vviuiam n. rai-iaith, Audubon, N. r. Appuatienmayai, 1939, serial No. 275,419

Myzinvention relates to automatic sprinkler systems for nre protection,employing a tank for supplying liquid to a distributing pipe, havingsprinkler heads. Air under pressure in the tank 11 is balanced by likepressure in said pipe above the level of the liquid. When a sprinklerhead opens, thepressure the tank forces the liquid through the `pipeandthe open heads.

'Heretofore a restricted air passage 4between the tank and the pipe hasbeen employed for allowing the pressure to equalize and maintain theliquid in the -pipe at the same level as in .the tankwhen leakage occursin .the system above the liquid in the pipe. When a sprinkler head wouldopen the air under pressure from the tank would continue toi'low throughsaid airpassage and retard the initial rise of liquid in the pipe. Means`have also Abeen employed for closing said air passage, which means Wereactuated by the rise of liquid, bythe opening of a sprinkler head, andtheiiow rof liquid was retarded by the air under pressure :beingadmitted to. the distributing pipe during the time'required for theliquid to rise tothe required level for closing said air passage. Theobject of my invention is to increase 'the speed of operation of thedischarge of liquid from they tank through the distributing pipe when asprinkler head opens.

A further object is to provide a system in which allftheair' underpressure is confined within the l tank for imparting arapid initial`movement oi the liquid from the tank to the distributing pipe, v andthe admission of air to said pipe from the tank above the liquid levelis entirely cut oi, so that therflow inl said pipe will not-be retarded`when a `sprinkler head opens, and all the air in theftank is utilizedforforcing the liquid from the tankA to the sprinkler heads.

A further object is to provide a normally closed valve in an air passagebetween the tank and the distributingfpipe for sealing the air in thetank so that a gradual 'change in the liquid' level in` the pipe will`occur in the event of leakage of air from the system above the liquidin the pipe.

,-A; further Vobject is Vto `provide valve opening means actuated by agradual rise ci liquid in the pipefor equalizing the pressure inthe tankand the pipe and thereby restoring the liquid level y in the pipe totheliquid level in the tank.

A further object is to construct said Vvalve opening means in the formof a float arranged within a chamber located above the normal liquidlevel in the pipe, so that the weight of the valve and the ioat willclose said valve when the prese claims. `(ci. isa-iv) tures ofconstructionand rarrangernent of the i which will oe more fullyhereinafter described and claimed constitute my invention.

Referring'to the accompanying drawing: Fig. l is a vertical sectionalview showing a sprinkler system embodying my invention.

Fig. 2 is a horizontal section on line 2 2 Fig. l. In the drawing in.which like reference characters refer to iike parte, 3 represents aclosed tankwhich is partlylled with liquid through a pipe d, and adaptedto contain air under pressure above the liquid. p

A distributing pipe, or riser, is connected at its lower end withthetankr il and is in communication with the lower portion of the latter.Said pipe (i 'forms part of' a close-d sprinkler systernv includingIbranch pipes l and automatic sprinkler headed.` A valve -casingl iscoupled between sections of the distributing pipe. Said casing has anaxial tubular core 23 forming a passageway in alignment with thesections of the p pi-pe 6. l i

The system is charged with Aair under pressure from a supply' pipe iii,having a check valve l5, through which the air is supp-lied tothe pipeii througha pipeV i6, and'supplied to the tank 3 through pipes i? andi.The pipe il is provided with a check valve i9. Said check valves i5 andit prevent `the flow of air toward the supply pipe lli. After` thesystem has been charged with air, the air supplythrough the pipe ifi isshut off 4by means of a suitable'valve, notV shown in the drawing. y

The casing it is provided: withr a sealed valve 'chamber 2d, which isconnected with the pipe iii,

communication with the distributingpipe V6 the buoyancy of thecontainer.

through apertures 3| and 32 formed in the core I2 of the casing. Thevalve 25 is arranged so as to be held closed upon its seat by apreponderance of pressure confined in the tank and in the chamber 20, inthe event of a sudden reduction of the pressure in the pipe 6, caused bythe opening of a head 8. Said valve 25 is automatically closed bygravity when the air pressure in the tank is equalized with the pressurein the pipe 6. The valve 25 is secured upon a stem 33 which extendsthrough the port 2 and into the iioat chamber 3G. A float 35 is securedto the lower end of the stem 33 and is adapted for lifting the valve 25from its seat when the-liquid rises in the pipe 6 and enters the floatchamber 30. When there is a slight reduction in the pressure in the pipe6, due to leakage of air from the latter, the liquid level in the pipe 5will rise gradually |by the action of the relatively higher pressureconnedl in the tank. When the liquid enters the chamber 35 it will liftthe float 35 and open the valve 25 against a slightly higher pressure inthe tank relatively to that in the pipe 6. When there is a greatdifference between the pressure in the tank relatively to that in thepipe 5, due to the opening of a sprinkler head, the differentialpressure acting upon the upper side of the valve 25 will be so greatthat the neat will not open said valve, thus conning all the air underpressure within the tank for forcing the liquid lfrom the tank throughthe pipe 5 to the open sprinkler head.

The float, or container 35, is cup-shaped so that it will be filled withliquid when the latter continues to rise in the pipe 6, thus negativingThe filling of the container with liquid will prevent the containeracting as a float and opening the valve 25, when the air pressure in thetank is nearly exhausted by the forcing ofthe liquid through the pipe 5lto the open sprinkler heads.

The casing I is provided with alarm apparatus 58, comprising a lever 39pivoted in av flexible bearing 46 mounted upon the 'casing above thelevel of the iioat 35. Said lever has. an arm il extending into a secondfloat chamber 42, and an arm 43 extending through the wall of the casingand arranged for tilting a mercury switch 55,

vfor controlling an` electric circuit including an alarm device 46.

A ball float lil is located in the chamber l2 formed within the casinglll and communicating with the pipe B through apertures 48 and 49 formedthrough the core l2. Said iioat lll' is adapted to engage the arm lll ofthe lever and actuate the alarm when the liquid continues to rise in thepipe B due to the opening of a sprinkler head, or due to the failureofthe valve 25 to open and the liquid continues to rise due to a slow leakin the pipe 6.

The operation ofy my invention is as follows: The tank 3 and the pipe 6are partly lled with liquid. Air under pressure is forced into the tankand the pipe above the liquid for iilling the system, which is closed bya sprinkler head, for' maintaining the liquid in the pipe at the same y`the liquid in the pipe 6 to a higher level than that inthe tank. y

When the liquid rises in the pipe 6 it will enter the chamber 30 andlift the float 35 `which will open the valve 25, so that the pressure inthe pipe will equalize with the pressure in the tank and thus restorethe liquid level in the pipe rto the liquid level in the tank, and thevalve 25 will close by its own weight when the pressure is equal onopposite sides of the valve.

Should the valve 25 fail to open, the liquid will continue to rise andoveriiow the container 35, so that the latter will not act as a float,and the valve 25 will remain closed in the event of a sprinkler headopening.

When the liquid rises above the top of the container 55 and lls thechamber 42, the ball iioat il will liftv the arm M and tilt the switch55, thereby closing the circuit and actuating the alarm for indicating arise of liquid in the pipe 6, caused by the opening of a head 8, or forindicating the failure of the valve 25 to open in the event of a slowreduction of pressure in the pipe 5 due to leakage.

Upon the opening of a sprinkler head the air under pressure will bereduced in the pipe 6 so that the valve 25 will be held lclosed upon itsseat by the relatively higher pressure in the tank, and all the airunder pressure in the tank will be conserved for forcing the liquid fromthe tank through the pipe S to the sprinkler heads.

I claim: y

1. A sprinkler system comprising a tank partly filled with liquid, adistributing pipe in communication with the lower portion of the tankand extending above the latter, said tank and pipe containing air underpressure above the liquid level, a connection forming an air passagebetween the tank and pipe` above the liquid level, means arranged fornormally closing said passage when the pressure in the pipe and tank areequal andfor sealing said passage by the action of a relatively higherpressure in the tank in the event of a sudden reduction in the pressurein the pipe, and means actuated by a gradual rise in the level of theliquid in said pipe for actuating said iirst named means for admittingthe pressure from the tank to said pipe and restoring the liquid levelin the pipe to that in the tank. 2. A sprinkler system comprising a tankpartly filled with liquid, a distributing pipe in communication with thelower portion of the `tank andA extending above the latter, saidl tankand pipe containing air under pressure above the liquid level, aconnection forming an air passage between the tank and said pipe, anormally closed valve controlling said passage 'for confining saidpressure within the tank, and means actuated by a gradual rise of theliquid level insaid pipe, due to leakage of air from the latter,arranged for opening the valve for equalizing the pressure in the pipeand tank.

3. A sprinkler system comprising a tank partly filled with liquid, adistributing pipe in communication with the lower portion of the tankand extending above the latter, said pipe and tank containing air underpressure above the liquid level, a connectiony formingan air passagebetween the tank and said pipe, a weighted valve normally closing saidpassage when the pressure in said pipe is equal to the pressure' in thetank, said valve arranged to be maintained closed by a preponderance ofpressure in the tank for sealing the latter upon the sudden reduction ofair under pressure from said pipe, and means for opening said valveactuated bya gradual rise of the liquid level, in said pipe, Vdue toVleakage of air from the latter, for equalizing the pressure in the pipeand tank and restoring the liquid level in the pipe to that in the tank.

4. A sprinkler system comprising a tank partly lled with liquid, adistributing pipe in communication with the lower portion of the tankand extending above the latter, said tank and pipe containing air underpressure, a connection forming an air passage between the tank and saidpipe above `the level of the liquid, a normally Closed valve controllingsaid passage for conning said pressure within the tank and causing arise of the liquid level in said pipe in the event of leakage of airfrom the latter, and a float actuated `by the rise of the liquid levelin said pipe and arranged for opening said valve for equalizing thepressure in said pipe and tank and restoring the liquid level insaidpipe to that in the tank.

5. A sprinkler system comprising a tank partly filled with liquid, adistributing pipe' in communi.- cation with the `lower portion of thetank vand extending above the latter, said tank and pipe containing airunder pressure, a connection forming an air passage between the tankand` said pipe above the liquid level, a normally closed valvecontrolling said passage for confining said pressure within the tank andcausing a rise of the liquid level in said pipe in the event of leakageof air from the latter, a float chamber in communication with said pipe,a cup shaped iioat located in said chamber above the normal liquidlevel, said float adapted for opening said valve upon a gradual rise ofthe liquid level in said pipek relatively to that in the tank,` and saidoat arranged to close said valve when the liquid continues to rise andlls saidcup shaped float.

6. A casing having inlet and outlet pipe connections, said casing havinga passageway formed through vthe same for the ow of liquid through saidconnections, said casing having a sealed air chamber formed therein, apipe connection through which air under pressure is supplied to saidchamber, said casing having a port forming a communication between saidchamber Y and said passageway, a valve within said chamber

